Posted on 03/15/2014 2:24:35 PM PDT by nickcarraway
If multiple communication systems aboard Flight 370 were manually disabled, as investigators increasingly suspect happened, it would have required detailed knowledge of the long-range Boeing777's inner workings.
The Wall Street Journal said the first loss of the jet's transponder, which communicates the jet's position, speed and call sign to air traffic control radar, would require disabling a circuit breaker above and behind an overhead panel.
Pilots rarely, if ever, need to access the circuit breakers, which are reserved for maintenance personnel.
Pulling one specific circuit breaker, which is labeled, would render inoperative both of the 777's transponders, according to documents reviewed by WSJ and bolstered by comments from aviation industry officials and those who have worked with the 777.
Becoming familiar with the 777's systems requires extensive training for pilots and aircraft mechanics alike, experts said. However, considerable technical data on the airplane is also available online in discussion groups or other websites.
Investigators are trying to establish a sequence of events that transpired on the jet, which vanished from radar March 8, most critically the loss of communication.
The shutdown of the on board reporting system shortly after the jet was last seen on radar, can be performed in a series of keystrokes on either of the cockpit's two flight management computers in the cockpit.
The computers are used to set the performance of the engines on takeoff, plan the route, as well as other functions to guide the 777.
After vanishing, the jet's satellite communications system continued to ping orbiting satellites for at least five hours.
The pings ceased at a point over the Indian Ocean, while the aircraft was at a normal cruise altitude, say two people familiar with the jet's last known position.
Investigators are trying to understand that loss, and whether or not "something catastrophic happened or someone switched off" the satellite communication system, says one of the people.
The longest week
A physical disconnection of the satellite communications system would require extremely detailed knowledge of the aircraft, its internal structure and its systems.
The satellite data system is spread across the aircraft and disabling it would require physical access to key components.
Disconnecting the satellite data system from the jet's central computer, known as AIMS, would disable its transmission. The central computer can be reached from inside the jet while it is flying, but its whereabouts would have to be known by someone deeply familiar with the 777.
Getting into the area housing the 777's computers would "not take a lot" of knowledge, said an aviation professional who has worked with the 777.
However, this person added, "to know what to do there to disable" systems would require considerable understanding of the jet's inner workings.
Some airlines outfit the access hatch to the area below the floor with a special screw to prevent unauthorized intrusion, the person added.
Orbiting satellites are designed to check in with the aircraft's satellite-communication system hourly if no data is received during that time.
The pings from the aircraft became a subject of scrutiny earlier this week, said a person familiar with the matter, several days after the plane first went missing.
Because the pings between the satellite and the aircraft registered that the aircraft's satellite communications system was healthy and able to transmit, the data did not immediately raise any red flags in the hours after the jet's disappearance.
At first, the origin of the final ping from the Malaysia Airlines jet seemed like an anomaly to investigators, according to a person familiar with the matter, given that the plane was believed to have crashed off the coast of Vietnam, hundreds if not thousands of miles from the location of the final ping.
What is a transponder? Until just a few years ago, the satellite communication system used by jetliners didn't include data on an aircraft's location in the pings, the electronic equivalent of handshakes used to establish initial contact.
For instance, before Air France Flight 447 crashed into the Atlantic Ocean in 2009, the jet sent some diagnostic data indicating problems with various onboard systems, including the autopilot's deactivation. But notably the plane's position wasn't transmitted with that data.
Partly as a result it took nearly two years to locate the plane's "black boxes" and the majority of the wreckage. In the case of the missing Malaysian jetliner, precise locations were provided. However, it is unclear why the transmission ceased and where the plane may have ended up after the final ping.
An expert would be needed to disable the systems on the missing Malaysia Airlines jet. The headline to an earlier version of this story incorrectly said an insider would be needed.
It is a transceiver, it is the cockpit, so yeah, it is good to be able to cut electrical power to something right next to you to keep it from burning.
“Seems like that logic could extend to shutting down the black box”
You can. They are not “essential” for flight or proper operation of the airplane. They’re helpful and beneficial but if they’re smoking, arcing, or, otherwise interfering with the safe operation of the airplane they can be turned off.
“or someone switched off” the satellite communication system, “
Well,,,, what about the radios? I’m curious as to what communications were sent to the plane. Of course the pilots didn’t answer any radio calls, but I’d bet they were listening!
I could figure it out
Those Amphenol connectors (green, round) are poorly terminated. Some don't even have backshells or strain relief. This is not what you do in a system that experiences vibration.
No indication that ACARS was disabled thus no expert required. Malaysia airlines does not subscribe to the ACARS so their pilots would not be familiar with it. Rolls Royce does have a subscription as part of their maintenance/support for the engines. On this flight there were three messages scheduled. One on takeoff, one upon initial cruise climb complete and one on landing. The second message was sent shortly before the aircraft diverted from plan. The third message was never received because (I assume) the aircraft never landed (crashing doesn’t count). The messages are not of immediate operational interest so they are sent at scheduled transmission windows. The SATCOM link stays active (who turns off their cable modem when they’re not watching television or surfing the Internet).
Not an Iridium satellite. Rather an Inmarsat geosynchronous satellite.
The final recorded ping at 8:11 KL time exceeded many earlier estimates for its potential time in flight. How much fuel was really loaded and those loading it should be investigated.
Comparing the possible positions at each recorded ping (only the last has been released to my knowledge) would also be interesting. Don't know why they haven't released the others, but I can dream the plane didn't move between the last two pings so is known down, it has been spotted and Uncle Mao is en route to the rescue. Or, if it went far enough, Uncle Vlad might rescue them—he could use the PR.
Some have suspected a Malaysian coverup. The co-pilot turns out to be the son of a high ranking civil servant. Powerful fathers can run coverups. Early reports described him as "religious" and "a good muslim" contrasting his behavior inviting girls into his cockpit. While those labels may sound good for local Malaysian audiences they'd raise different issues here.
Getting to the final ping site, at least to the more interesting northern option (and who'd elaborately plan a slow suicide) means avoiding many radars. Either defenses there are much worse than presumed or the perps had the knowledge and skill to evade them. Determining what the perps could have known about those defenses and reverse engineering their possible routes may be enlightening. In the least it would be a good exercise for some bright military pilots.
I believe today the Malaysians stated that in fact the ACARs was turned off and, according the timing of it, that the person making the “All right, good night” radio call to KUL ATC was not the person doing it. As disabling the ACARs would be done in another part of the airplane that then indicates that someone was in the cockpit talking to ATC at roughly the same time someone else was manually turning it off elsewhere in the plane.
Ugh.....
My Verizon cell phone works reliably from cruising altitude, but my previous Sprint phone did not. (NB: non-passenger airplane!)
The whole thing adds to another dimension of fear. People would at least console themselves that a hijacking would mean a quick end.
That is what was thinking also ... The only ping missing would be at landing gear down for touchdown. Doubt anyone could say for certain was disabled.
Since scheduled arrival in Beijing was 0630 and last ping was 0811 it is consistent with the aircraft carrying enough reserve fuel for a diversion airport plus 45 minutes for traffic holds.
Malaysian misunderstanding of ACARS. There was no simultaneous turning off of ACARS while pilot is radioing goodbye. The last transmission of ACARS was just that: a text message then silence because ACARS wasn’t scheduled to send any more texts until the plane landed. No need for a second person to be climbing down into the electronics bay. One nan job.
Maybe not the transponder but that could be turned off by a breaker behind a panel in the cockpit. It would require expert knowledge but not difficult.
Does it work over the ocean? I don’t think so... when you’re cruising at altitude over land, you are only 7 miles in the air. Add in a little horizontal distance, and you might still be no more than 10 or 12 miles from the tower. In the middle of the ocean... you’re hundreds of miles from any tower—you can’t connect.
If you don’t believe me, try to use a US cellphone on a cruise boat. It stops working an hour or two out of port (not counting using the outrageously expensive on-ship link).
I presume the pings would end when the plane is powered down or when it is within a hanger, so we don't have to presume a crash ended them. Otherwise we'd have to presume the perps knew about and actively ended the pings, with whatever that implies, or accept a crash scenario.
There you go, a lot neater than the sloppily labeled fuse box in my house and somehow I manage to turn things off.
So, you can find that in a matter of minutes. Meanwhile we are “crowd sourcing” people to search satellite imagery in the Himalayas. Are they crowd sourcing people to search at the last radar location? Nope.
What if in addition to the things that were turned off the interior lights and navigation lights were also turned off. Let’s say that was confirmed by a fighter jet and when an attempt was made to make visual contact the airliner took some evasive action?
Sooner or later some government or group of governments was going to be faced with the decision to down a rogue airplane. The socioeconomic aftermath is incalculable. A coverup in in everyone’s interest and possibly this is why 10 countries are searching for a plane nobody wants to find.
It’s also a distinct possibility that governments that colluded in the decision are now flat denying any involvement (China & Vietnam).
At the last known radar contact the water depth is about 170 feet at most. Dangerous but doable even for a recreational diver. Remember, there’s no crowds sourcing of images there. Nine days to recover enough debris to befuddle any future investigate. This all serves the greater good.
The ping was turned off over a larger body of water to make the search area huge, then my bet is the plane flew to Islamabad. Malaysian Airlines flies there anyway.
Islamists will load a nuke on it and fly it into Tel Aviv.
Obama obviously could care less about a stolen plane to be used on the Jews. He could, through his Muslim Brotherhood connections, even know about the plan already.
Would Israel shoot down a “lost” passenger jet flying in their direction?
At any rate, it will take a while to get the “bomber” ready.
It probably needs a new paint job.
“The Wall Street Journal said the first loss of the jet’s transponder, which communicates the jet’s position, speed and call sign to air traffic control radar, would require disabling a circuit breaker above and behind an overhead panel.”
Absolute BS.
The transponder has a four position switch. OFF STBY ON ALT or Off Standby On and Altitude. You simply move the switch, located on the center console, to off or standby.
Would that even have been necessary? I bet it wasn't the first civilian plane to end up in airspace where it wasn't supposed to be. My guess is that most military radar personnel just let these things slide on the assumption that somebody down the line forgot to file his paperwork ahead of time. Who wants the infamy associated with shooting down a civilian plane?
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